Lighter-tham-air aircraft



May 31,1921.

. 1,630,726 B. N. WALLIS LIGHTERTHAN'AIR AIRCRAFT Patented May FWESTMINSTER, LONDON,

ANY, LIMITED, 013 WESTMKNSTEB, ENGLAND.

BARNES NEVILLE \VIALLIS, 0

SHIP GU Application filed December 16, 1925, Serial No.

This invention aircratt.

AHANTEE COMP Parana." orricn.

LETEQ'GLAND, ASSIGNOR TO AIR- LIGHTLllR-THAN-AIIE ATERCRAFT.

relates to lighter-than-air At the present time the outer cover'orenvelope oi an airship is usually maintained taut by the combined use oidope and a sys= tem of lacing. is impossible by certain degree of pingor increased occurs, during continued use, owing terioration in theApart from the tact that it this method to prevent a sagging at anyti1ne,"['lap sagging of the outer cover to dedope or to slackening oithe lacing, thereby distortingthe contour or outer surface oi theairslnp and reducing its speed and sensitiveness to control.

According to the present invention outer cover of an by result maybetween the outer communication inflating or distending the same.

be obtained by placing the space with means of air scoops or openings,

the airship is maintained taut This cover and the gas bags in theatn'iosphere by usually located in the neighbourhood of the nose of theairship, so that the outer cover is distended by air pressure.

Alternatively, a

mechanical blowing engine may be develcontent, may any or all of ployed.even at moderate else the exhaust either betore or their water oped forthe purpose, or

speeds the pressure of the air at the nose of the airship will beadequate to secure the desired result, and, when the ship is moored, thecover will main tight if the ever, there is not cover taut and it tautor prevent moored, a. mechanical blowing also rere is any wind. It,howsufiicient wind to keep the should it be desired to. keep saggingwhen the ship is engine may be provided on the airship, or on, oradjacent to, the moo these conditions.

where provision is made for using ring mast for use under Alternatively,and in cases the exhaust gases of the engines the same result may beattained 5 either by running s faster with the clutches out.

method or methods of maintaining when the ship is moored the enginesslowly or The aforesaid the outer cover taut may also be employed inconjuno tron with any of the usual methods by which attempts have beenmade in the past to maintain the outer cover taut, e. g., or the use ofdopes.

between the gas lacing If desired, the space bags and the outer cover75.884, and in Great Britain January 21, 1925.

may be divided into independent sections each of which placed incommunication with the atmosphere by'an air scoop or aperture at thenose of the airship. In the case of a rigid airship o'l polygonal crosssection, the outer cover need the longitudinal frames. As there will bea slight leakage of the high pressure air through various openings inthe outer cover to the atmosphere which will cause a certain amount ofair to circulate in the space between the gas bags and the outer coverthe use of the present invention also has the advantage that it coolsthe gas bags and ventilates the space between the gas bags and the outercover, so that the usual ventilators or air scoops can dispensed with.The usual air scoops are in themselves objectionable,,as theyformprotuberances Wl1lCl1-l11 tcrtere with the streamline flow aroundand along the hull or body, and, as the present invention enables theseprotuberaiices' to be dispensed with, the speed of the airship and itssensitiveness to control is increased.

Furthermore, although attempts have been made to construct an airshiphavii'ig one of the most approved streamline forms, the advantagesderived from the adopt-ion of such streamline form are detracted fromowing to sagging of the outer cover which results from the usual methodsof maintaining the outer cover taut. On the other hand, the presentmethod of maintaining the outer cover taut also has the advantage thatit allows an airship to be constructed having the most approvedstreamline form, and to allow such streamline form to be maintained atall times when the airship is in flight. For example, it is known that abody having a ratio of overall length to maximum diameter of l or 5 to 1will otter a very low resistance to propulsion through the air providedthe followingproportions are generally maintained (a) The head or frontportion is approximately only be attached along the outer cover tauttheaforesaid streamline shape can be produced and maintained during flightby connecting the outer cover tofixed portions of the airship,such asthe longitudinal frames, such connecting means being oi such a length orcharacter, and bc- 111g so arranged that under the influence of the airpressure in the space between the has bags and the outer cover thelatter will take up and maintain during flight the desired. streamlineshape. i

The aforesaid method of maintaining the outer cover of an airship tautcan advantageously he used in combination with the i invention describedin ourro-pending apthe airship where there exists high relative velocityand zero ornegative pressure. Instead of a single opening as shown twoor more openings may be provided at the ex treme nose of the airship soas to place the space A between the outer cover B and the gas bags G inconnnunication with the at mosphere. In the example illustrated in thedrawing a number of separate air compartments are provided along thelength of the 7 ments G, G, alone; the length ol' the ship, '15 thecompartn'ients G being; formed by dividing up the air space A atsuitable distances apart into separate chambers by .lurants of fabricbulkheads H, H. i l

What I claim and desire to secure by l'ict' 4511 tors Patent of theUnited fi trates isz I. A method of n'iainfizainiug taut the outer coverof an airship which consists in prr" riding a space completelysari-minding the gas bags and located between the outer cover and thegas bags, said space being); placed in couununiczuion with thefiikfliielllltrl' by air admission means situated at theextrehic nose ofthe airship in the region of unrximuim pressure and zero relocityso thatthe oilhiir cover is distended by the air pressure at the nose of theship. a a p 2. A method of niaintaiilinp" taut the outta cover of anairship which consists in pro viding a space completely e1irrouiidiunthe gas bags and located hetwecuthc outer, and the gas bags, said spacebeing:divu into independent sections mich oi" which it placed incommunication with thcjfl'itimis phere by air admission means situatedat the extreme nose of the airship in the ri-p'ion pi. maximum pressureand zero rehiicity so th it the outer cover is distended by the air prssure at the nose of the ship. a r

BARNES NEVILLE mm;

